shinya yamanaka built on that and went further. he was able to turn mature cells back into their earliest form as primitive cells. those cells are in many ways the equivalent of embryonic stem cells because they have the potential to develop into specialized cells. for heart, liver and other organs. dr. shinya yamanaka is currently working at kyoto university. embryonic stem cells have had to be harvested from human embryos, a source of debate and considerably controversy. for gurdon the prize at special meaning. at a news conference in london he recalled one school teacher's reaction to his desire to study science. >> it was a completely ridiculous idea because there was no hope whatever of my doing science. and any time spent on it would be a total waste of time both on my part and the part of the peinonav hg to teach him. so that terminated my completely... completely terminated my science at school. >> suarez: the men will receive their award in stockholm in december. for some detail on the science and the men behind today's pr